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arXiv · 2011.02447

Epitaxial integration of improper ferroelectric h-YMnO$_3$ thin films in heterostructures

J. Nordlander·M. D. Rossell·M. Campanini·M. Fiebig·M. Trassin
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Abstract

We report on multiple fundamental qualitative improvements in the growth of improper ferroelectric hexagonal YMnO$_3$ (YMO) thin films and heterostructures by pulsed laser deposition (PLD). By a combination of pre-growth substrate annealing and low-energy-fluence PLD, we obtain a two-dimensional growth mode of the YMO films on yttria-stabilized zirconia (YSZ) with ultralow roughness and devoid of misoriented nanocrystalline inclusions. By inserting a sacrificial manganite layer capped with conducting indium-tin oxide between the substrate and the final film, the latter is grown in a fully lattice-relaxed mode and, thus, without any misfit dislocations while maintaining the extraordinary flatness of the films grown directly on pre-annealed YSZ. This provides a template for the fabrication of heterostructures based on hexagonal manganites as promising class of multiferroics with improper room-temperature ferroelectricity and the implementation of these into technologically relevant epitaxial metal|ferroelectric-type multilayers.

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J. Nordlander, M. D. Rossell, M. Campanini, M. Fiebig, M. Trassin. 2020-11-04. Epitaxial integration of improper ferroelectric h-YMnO$_3$ thin films in heterostructures. https://doi.org/10.1103/physrevmaterials.4.124403

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